Threats

Threats

Major Threats

As this species generally forages over oceanic waters it is less likely to encounter longline fisheries targetting Patagonian toothfish in shelf areas, although mortality of breeding birds is still recorded in these fisheries34. In Australian waters, up to c.400 individuals (>80% juvenile) were killed annually in 1989-1995 by Japanese longliners8. In the Indian Ocean, illegal or unregulated fishing for Patagonian toothfish Dissostichus eleginoides killed an estimated 10,000-20,000 albatrosses (mainly this species) in 1997 and 19981,2,18. At Campbell, the long-term decline, which began well before local longline fishery development, appears to be caused by environmental factors, possibly rising sea-surface temperatures resulting in food shortages, but longline fisheries beyond the New Zealand Exclusive Economic Zone (EEZ) may also contribute14. The species is not caught on fishing vessels monitored by New Zealand observers within the EEZ28. Outside of EEZs, due to its circumpolar distribution, T. chrysostoma is potentially vulnerable to Southern Ocean pelagic fisheries worldwide. The extensive use of the Subtropical Convergence and Subantarctic Zones by incubating birds from Marion Island, especially females, bring them into contact with intense southern bluefin tuna Thunnus maccoyii longline fishing activity in international waters (40-45°)34.